During the drilling and production of oil and gas wells, it may be necessary to manage high pressure fluids in the well. The subject matter disclosed herein relates to methods and apparatus for controlling pressure within a wellbore. In particular, embodiments disclosed herein include methods and apparatus for operating ram-type blowout preventers and the equipment associated with installation and maintenance of the ram block.
Blowout preventers are used in hydrocarbon drilling and production operations as a safety device that closes, isolates, and seals the wellbore. Blowout preventers are essentially large valves that are connected to the wellhead and comprise closure members capable of sealing and closing the well in order to prevent the release of high-pressure gas or liquids from the well. One type of blowout preventer used extensively in both low and high-pressure applications is a ram-type blowout preventer. A ram-type blowout preventer uses two opposed closure members, or rams, disposed within a specially designed housing, or body. The blowout preventer body has a bore that is aligned with the wellbore. Opposed cavities intersect the bore and support the rams as they move into and out of the bore. A bonnet is connected to the body on the outer end of each cavity and supports an operator system that provides the force required to move the rams into and out of the bore.
The rams are equipped with sealing members that engage to prohibit flow through the bore when the rams are closed. The rams may be pipe rams, which are configured to close and seal an annulus around a pipe that is disposed within the bore, or may be blind rams or shearing blind rams, which are configured to close and seal the entire bore. A particular drilling application may require a variety of pipe rams and blind rams. Therefore, in many applications multiple blowout preventers are assembled into blowout preventer stacks that comprise a plurality of ram-type blowout preventers, each equipped with a specific type of ram.
Ram-type blowout preventers are often configured to be operated using pressurized hydraulic fluid to control the position of the closure members relative to the bore. Although most blowout preventers are coupled to a fluid pump or some other active source of pressurized hydraulic fluid, many applications require a certain volume of pressurized hydraulic fluid to be stored and immediately available to operate the blowout preventer in the case of emergency.
Thus, the embodiments disclosed herein are directed to ram-type blowout preventers that seek to overcome limitations of the prior art in handling removeable ram blocks.